Differential Diagnosis for the Patient's Headache
The patient presents with a severe headache that began at the back left side of her head and now radiates to her forehead, accompanied by moderate tenderness to palpation of the left occiput and upper cervical muscles, and increased sensation to light touch and pinprick over the left side of the head. Based on these symptoms, the following differential diagnoses are considered:
Single Most Likely Diagnosis
- Transformed Migraine (D): This is the most likely diagnosis given the patient's severe headache with a new pattern, lack of previous similar headaches, and the presence of neck pain and tenderness. The headache's progression and the patient's history of moderate neck pain treated with chiropractic manipulation and ibuprofen support this diagnosis.
Other Likely Diagnoses
- Compression Neuropathy (A): Given the patient's history of neck pain and chiropractic manipulation, compression neuropathy, particularly of the occipital nerve, could be a contributing factor to her headache. The increased sensation to light touch and pinprick over the left side of the head also supports this possibility.
- Temporal Arteritis (C): Although less likely due to the patient's age and lack of other systemic symptoms such as jaw claudication or visual disturbances, temporal arteritis cannot be entirely ruled out without further investigation, including an erythrocyte sedimentation rate (ESR) test.
Do Not Miss Diagnoses
- Subarachnoid Hemorrhage (B): This is a medical emergency that requires immediate attention. Although the patient's presentation does not strongly suggest subarachnoid hemorrhage (e.g., no reported "thunderclap" headache, no loss of consciousness, and normal vital signs), it is crucial to consider and rule out this condition due to its high morbidity and mortality.
- Venous Sinus Thrombosis (E): Another potentially life-threatening condition, venous sinus thrombosis, should be considered, especially if there are risk factors such as hypercoagulability, pregnancy, or oral contraceptive use. However, the patient's presentation does not strongly suggest this diagnosis.
Rare Diagnoses
- Other rare causes of headache, such as arteriovenous malformations, cerebral vasculitis, or certain infections, are less likely given the patient's presentation and history. These would typically require specific risk factors or additional symptoms not mentioned in the case.